Vaccine HBsAg

Infants born to HBsAg-positive mothers should receive hepatitis B vaccine and 0.5 mL hepatitis B immune globulin (HBIG) within 12 hours of birth at separate sites. The second dose is recommended at age 1-2 months and the vaccination series should be completed (third or fourth dose) at age 6 months. 

Infants born to mothers whose HBsAg status is unknown should receive the first dose of the hepatitis B vaccine series within 12 hours of birth. Maternal blood should be drawn at the time of delivery to determine the mother s HBsAg status if the HBsAg test is positive, the infant should receive HBIG as soon as possible (no later than age 1 week). 

The two hepatitis B vaccines available in the United States are Recombivax HB and Engerix-B. These vaccines are produced with recombinant DNA technology by inserting the gene for HBsAg into the plasmid that is synthesized by Saccharomyces cerevisiae cells. Both vaccines are effective in providing... 

Postexposure prophylaxis for perinatal exposure depends upon the mother s HBsAg status.24 Mothers who are HBsAg-positive should have their newborns immunized with both the hepatitis B vaccine and HBIG 0.5 mL. This regimen is 85% effective in preventing the hepatitis B carrier status if administered... 

Exposed Person s Vaccination Status HBsAg Positive HBsAg Negative Unknown or Unavailable for Testing... 

Previously vaccinated Known responder Known non-responder Antibody response unknown No treatment HBIG x 1 and initiate HB revaccination or HBIG x 2 Test exposed person for anti-HBs (1) if adequate, no treatment (2) if inadequate, HBIG x 1 and vaccine booster No treatment No treatment No treatment No treatment If known high-risk source, treat as if source were HBsAg-positive Test exposed person for anti-HBs (1) if adequate, no treatment (2) if inadequate, vaccine booster and recheck titer in 1-2 months... 

Hepatitis B vaccine is manufactured using recombinant DNA technology to express hepatitis B surface antigen (HBsAg) in yeast. This is further purified with biochemical separation techniques to produce the vaccine. The vaccines are formulated to contain 10 to 40 meg of HBsAg protein/mL. Hepatitis B vaccine is available as a single component or in combination vaccines. 

Hepatitis B surface antigen (HBsAg) Tobacco leaf Mice vaccinated parenterally produced all IgG subclasses and IgM. - 3,56... 

Figure 13.10 Overview of the production of recombinant HBsAg vaccine (Recombivax HB Merck). A single dose of the product generally contains 10 pig of the antigen...

Engerix B (tradename) is a subunit vaccine containing purified recombinant hepatitis B surface antigen (HBsAg) that gained approval in the USA in 1998. It is indicated for active immunization against infection caused by all known serotypes of hepatitis B virus. 

HBsAg (-) Immune because of vaccination (valid only if test performed 1-2 months after... 

Natural source may carry risk of infection. Recombinant Factor VIII used to treat hemophilia A has helped reduce the incidence of HIV infection in hemophiliacs. Recombinant HbsAg is now used to immunize against hepatitis B, eliminating the risk of introducing a viral infection during vaccination. 

Hepatitis B vaccine Suspension of hepatitis B surface antigen (HBsAg) purified from the plasma of hepatitis B sufferers Active immunization against hepatitis B (note this preparation has largely been superseded by HBsAg preparations produced by genetic engineering)... 

HBsAg was the first viral antigen to be produced in transgenic plants. The protein self-assembles into subviral mammalian particles of 22 nm, and is virtually indistinguishable from serum-derived and yeast-derived HBsAg in both infected sera as well as commercial vaccines with respect to size, density sedimentation, and immunogenicity. 

Plant cell culture has been used extensively for the production of biopharmaceuticals. A few examples are illustrated here, and a more extensive list can be found in Table 6.4. Smith et al. (2002) employed both soybean and tobacco cell lines to produce a hepatitis virus surface antigen (HBsAg), to be used as a vaccine, in shaker flask cultures. The authors found that the titers of HBsAg in soybean cell culture were 65 pg/g fresh weight, and 10-fold lower in tobacco cell culture, resulting in productivities of 1 mg/L/d and 0.16 mg/L/d, respectively. These numbers correspond well with those found for yeast batch cultures (1.5 mg/L/d). 

GenHevac B (HbsAg) Hepatitis B vaccine rCHO, microcarriers... 

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